<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Get请求</title>
</head>
<style>
    .box{
        width: 300px;
        height: 300px;
        border:1px solid black;
    }
</style>
<body>
    <button>发送请求</button>
    <div class="box"></div>
</body>
<script>
    addEventListener('load',function(){
 const btn=document.querySelector('button');
 const box = document.querySelector('.box');
 btn.addEventListener('click',function(){
    const xhr = new XMLHttpRequest();
    xhr.open('GET','http://127.0.0.1:8000/get?a=1&b=2&c=3');
    xhr.send();
    xhr.onreadystatechange = function(){
        if(xhr.readyState ===4){
            if(xhr.status >= 200&&xhr.status <300){
                console.log(xhr.status);//状态码
                console.log(xhr.statusText);//状态字符串
                console.log(xhr.getAllResponseHeaders());//所有响应头
                console.log(xhr.response);//响应体
             box.innerHTML = xhr.response;
            }
        }
    }
 })
 })
</script>
</html>